U.S. patent application number 09/916107 was filed with the patent office on 2002-02-21 for air bag in use for head protection air bag device.
Invention is credited to Ohno, Mitsuyoshi, Tanabe, Choko, Tanase, Toshinori, Urushi, Norio.
Application Number | 20020020991 09/916107 |
Document ID | / |
Family ID | 18724921 |
Filed Date | 2002-02-21 |
United States Patent
Application |
20020020991 |
Kind Code |
A1 |
Tanase, Toshinori ; et
al. |
February 21, 2002 |
Air bag in use for head protection air bag device
Abstract
An air bag is stored in the upper fringe of the openings on the
cabin-inside side, while being folded. The air bag includes a gas
inflow part for flowing inflation gas into the air bag, and a main
body which inflates when receiving the inflation gas. The main body
includes front- and rear-seat inflation chambers, and a gas passage
extending forward from the gas inflow part and allowing the
inflation gas to flow from inflow ports opened in the upper parts
of the front-and rear-seat inflation chambers to the front- and
rear-seat inflation chambers per se. The inflow port of the
rear-seat inflation chamber is opened in a direction substantially
orthogonal to an axial direction of the gas passage. A front-side
peripheral edge is disposed to be higher than a rear-side
peripheral edge.
Inventors: |
Tanase, Toshinori;
(Nishikasugai-gun, JP) ; Tanabe, Choko;
(Nishikasugai-gun, JP) ; Ohno, Mitsuyoshi;
(Anjyo-shi, JP) ; Urushi, Norio; (Toyota-shi,
JP) |
Correspondence
Address: |
PILLSBURY WINTHROP LLP
1600 TYSONS BOULEVARD
MCLEAN
VA
22102
US
|
Family ID: |
18724921 |
Appl. No.: |
09/916107 |
Filed: |
July 27, 2001 |
Current U.S.
Class: |
280/730.2 |
Current CPC
Class: |
B60R 21/232 20130101;
B60R 2021/23316 20130101 |
Class at
Publication: |
280/730.2 |
International
Class: |
B60R 021/22 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 31, 2000 |
JP |
2000-232201 |
Claims
What is claimed is:
1. An air bag in use for a head protection air bag device in which
said air bag, while being folded, is stored in an upper fringe of
openings on a cabin-inside side of a vehicle, said air bag
comprising: a gas inflow part for flowing inflation gas; a gas
passage extending forward from said gas inflow part; a front-seat
inflation chamber located at a position near a side of a front seat
for receiving the inflation gas; and a rear-seat inflation chamber
located at a position near a sides of a rear seat for receiving the
inflation gas, said front- and rear-seat inflation chambers being
disposed below said gas passage through respective inflow ports
formed in upper parts of said front- and rear-seat inflation
chambers to allow the inflation gas to flow into said front- and
rear-seat inflation chambers; wherein said inflow port of said
rear-seat inflation chamber is opened in a direction substantially
orthogonal to an axial direction of said gas passage, and its
front-side peripheral edge is disposed to be higher than its
rear-side peripheral edge.
2. An air bag in use for a head protection air bag device according
to claim 1, wherein said front-side peripheral edge is higher than
said rear-side peripheral edge by a dimension of 20 mm.
3. An air bag in use for a head protection air bag device according
to claim 1, wherein a height dimension of said front-side
peripheral edge from said rear-side peripheral edge is in a range
of 15 to 40% of a height dimension of said gas passage.
4. An air bag in use for a head protection air bag device according
to claim 1, further comprising a partitioning part parting said gas
passage from said rear-seat inflation chamber to thereby define
said inflow port of said rear-seat inflation chamber, said
partitioning part comprising a beginning part and a linear part
linearly slanting downward from said beginning part in a frontward
direction and said rear-side peripheral edge of said inflow port of
said rear-seat inflation chamber is positioned at a fore end of
said linear part.
5. An air bag in use for a head protection air bag device according
to claim 1, further comprising a partitioning part parting said gas
passage from said rear-seat inflation chamber to thereby define
said inflow port of said rear-seat inflation chamber, said
partitioning part comprising a beginning part and a linear part
linearly slanting downward from said beginning part in a rearward
direction and said front-side peripheral edge of said inflow port
of said rear-seat inflation chamber is positioned at a fore end of
said linear part.
6. An air bag in use for a head protection air bag device according
to claim 1, further comprising a guide formed on an upper
peripheral wall of said gas passage located above an inflow port of
said front-seat inflation chamber such that the upper peripheral
part is gently projected downward in a frontward direction.
7. An air bag in use for a head protection air bag device according
to claim 6, wherein a projection quantity between a lower end of
said guide and said upper peripheral wall of said gas passage is
set at 30 mm.
8. An air bag in use for a head protection air bag device according
to claim 6, wherein a projection quantity between a lower end of
said guide and said upper peripheral wall of said gas passage is in
a range of 20 to 50% of a height dimension of said gas passage.
9. An air bag in use for a head protection air bag device in which
said air bag, while being folded, is stored in an upper fringe of
openings on a cabin-inside side of a vehicle, said air bag
comprising: a gas inflow part for flowing inflation gas; a gas
passage extending forward from said gas inflow part; a front-seat
inflation chamber located at a position near a side of a front seat
for receiving the inflation gas; and a rear-seat inflation chamber
located at a position near a sides of a rear seat for receiving the
inflation gas, said front- and rear-seat inflation chambers being
disposed below said gas passage through respective inflow ports
formed in upper parts of said front- and rear-seat inflation
chambers to allow the inflation gas to flow into said front- and
rear-seat inflation chambers; and a guide formed on an upper
peripheral wall of said gas passage located above an inflow port of
said front-seat inflation chamber such that the upper peripheral
part is gently projected downward in a frontward direction.
10. An air bag in use for a head protection air bag device
according to claim 9, wherein a projection quantity between a lower
end of said guide and said upper peripheral wall of said gas
passage is set at 30 mm.
11. An air bag in use for a head protection air bag device
according to claim 9, wherein a projection quantity between a lower
end of said guide and said upper peripheral wall of said gas
passage is in a range of 20 to 50% of a height dimension of said
gas passage.
12. An air bag in use for a head protection air bag device
according to claim 9, wherein said inflow port of said rear-seat
inflation chamber is opened in a direction substantially orthogonal
to an axial direction of said gas passage, and its front-side
peripheral edge is disposed to be higher than its rear-side
peripheral edge.
13. An air bag in use for a head protection air bag device
according to claim 12, wherein said front-side peripheral edge of
said rear-seat inflation chamber is higher than said rear-side
peripheral edge by a dimension of 20 mm.
14. An air bag in use for a head protection air bag device
according to claim 12, wherein a height dimension of said
front-side peripheral edge from said rear-side peripheral edge is
in a range of 15 to 40% of a height dimension of said gas
passage.
15. An air bag in use for a head protection air bag device
according to claim 12, further comprising a partitioning part
parting said gas passage from said rear-seat inflation chamber to
thereby define said inflow port of said rear-seat inflation
chamber, said partitioning part comprising a beginning part and a
linear part linearly slanting downward from said beginning part in
a frontward direction and said rear-side peripheral edge of said
inflow port of said rear-seat inflation chamber is positioned at a
fore end of said linear part.
16. An air bag in use for a head protection air bag device
according to claim 12, further comprising a partitioning part
parting said gas passage from said rear-seat inflation chamber to
thereby define said inflow port of said rear-seat inflation
chamber, said partitioning part comprising a beginning part and a
linear part linearly slanting downward from said beginning part in
a rearward direction and said front-side peripheral edge of said
inflow port of said rear-seat inflation chamber is positioned at a
fore end of said linear part.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an air bag in use for a
head protection air bag device. More particularly, the invention
relates to an air bag which, while being folded, is stored in the
upper fringe of the openings on the cabin-inside side, and develops
and inflates to cover the openings when receiving the inflation
gas, and includes front- and rear-seat inflation chambers located
at positions near the sides of front and rear seats.
[0003] The present application is based on Japanese Patent
Application No. 2000-232201, which is incorporated herein by
reference.
[0004] 2. Description of the Related Art
[0005] A conventional head protection air bag device is constructed
with an air bag and an inflator of the cylinder type for supplying
inflation gas to the air bag (DE 29806200 Ul and GB 2324068, and
the like).
[0006] The air bag, while being folded, is stored in the upper
fringe of the openings on the cabin-inside side, and develops and
inflates to cover the openings when receiving the inflation gas,
and includes front- and rear-seat inflation chambers respectively
located at positions near the sides of front and rear seats.
[0007] The air bag includes a gas inflow part which is located at
the rear upper part and coupled to an inflator so as to flow
inflation gas from the rear side into the air bag per se, and a
main body including a front-seat inflation chamber and a rear-seat
inflation chamber, and develops and inflates to cover the openings
when receiving the inflation gas.
[0008] In addition to the front- and rear-seat inflation chambers,
the air bag further includes a gas passage extending forward from
the gas inflow part and being disposed above the front- and
rear-seat inflation chambers and allowing the inflation gas to flow
from inflow ports opened in the upper parts of the front- and
rear-seat inflation chambers to the front- and rear-seat inflation
chambers per se.
[0009] In the conventional head protection air bag device, the gas
passage is extended forward from the gas inflow part linearly and
substantially horizontally.
[0010] With this, the gas passage is filled, to a certain extent,
with inflation gas over its entire length, and then the inflation
gas flows into the front- and rear-seat inflation chambers via
inflow ports associated therewith. There is room for improvement in
quickly start the developing and inflating of the folded front- and
rear-seat inflation chambers below.
[0011] In particular above the rear-seat inflation chamber, the
inflation gas flowing forward through the gas passage is strong.
Accordingly, in the initial stage of the passage of the inflation
gas, inflation gas sometimes is hard to flow into the rear-side
peripheral edge. Accordingly, there is room for improvement in
securing a quick start of the downward developing/inflating
operation.
[0012] A possible measure taken for this is to change the gas
flowing passage so as to end the developing/inflating operation of
the rear-seat inflation chamber and to develop and inflate the
front-seat inflation chamber. This measure, however, further delays
the ending of the developing/inflating operation of the front-seat
inflation chamber which is likely to delay its developing/inflating
operation, because the front-seat inflation chamber is remote from
the gas inflow part.
SUMMARY OF THE INVENTION
[0013] Accordingly, an object of the present invention is to
provide an air bag in use for a head protection air bag device
which lessens a delay of the ending of a developing/inflating
operation of a front-seat inflation chamber, and quickly starts a
developing/inflating operation of a rear-seat inflation
chamber.
[0014] To achieve the above object, there is provided an air bag in
use for a head protection air bag device in which the air bag,
while being folded, is stored in the upper fringe of the openings
on the cabin-inside side, and includes a gas inflow part, located
at the rear upper part, for flowing inflation gas into the air bag
and a main body which develops and inflates to cover the openings
when receiving the inflation gas, the main body including front-
and rear-seat inflation chambers, located at positions near the
sides of front and rear seats, for receiving inflation gas, and a
gas passage extending forward from the gas inflow part and being
disposed above the front- and rear-seat inflation chambers and
allowing the inflation gas to flow from inflow ports opened in the
upper parts of the front- and rear-seat inflation chambers to the
front- and rear-seat inflation chambers per se. The air bag is
improved such that the inflow port of the rear-seat inflation
chamber is opened in a direction substantially orthogonal to an
axial direction of the gas passage, and a front-side peripheral
edge is disposed to be higher than a rear-side peripheral edge.
[0015] The air bag thus constructed may have such a preferable
construction that a plurality of inflow ports of the front-seat
inflation chamber are opened in a direction substantially
orthogonal to an axial direction of the gas passage, while being
arrayed along the gas passage, and a guide is formed on the
peripheral wall of the gas passage located above the plurality of
inflow ports for the front-seat inflation chamber, and directs
downward part of the inflation gas flowing forward and guides the
inflation gas from the inflow port of the rear-seat inflation
chamber into the front-seat inflation chamber.
[0016] In the air bag thus constructed, inflation gas flows from
the gas inflow part into the main body. Then, the inflation gas
passes through the gas passage extending forward and flows forward.
As recalled, the inflow port of the rear-seat inflation chamber is
opened in a direction substantially orthogonal to an axial
direction of the gas passage, and a front-side peripheral edge is
disposed to be higher than a rear-side peripheral edge.
Accordingly, the front-side peripheral edge of the inflow port is
easy to interfere with the inflation gas by an extent corresponding
to the dimension by which the front-side peripheral edge is higher
than the rear-side peripheral edge. The front-side peripheral edge
directs the inflation gas resulting from the interference to the
rear-seat inflation chamber. This leads to a quick start of the
developing/inflating operation of the rear-seat inflation
chamber.
[0017] The inflow port of the rear-seat inflation chamber has
merely such a configuration that it is opened in the direction
substantially orthogonal to the axial direction of the gas passage,
and its front-side peripheral edge is higher than its rear-side
peripheral edge. Such a configuration of the inflow port cannot
direct the entire inflation gas flowing forward within the gas
passage to the rear-seat inflation chamber, as a matter of course.
Therefore, a delay of the ending of the developing/inflating
operation of the front-seat inflation chamber may be minimized by
appropriately adjusting a height of the front-side peripheral edge
from the rear-side peripheral edge.
[0018] Accordingly, the air bag of the embodiment which is used for
the head protection air bag device is capable of minimizing the
delay of the ending of the developing/inflating operation of the
front-seat inflation chamber, and quickly starts the
developing/inflating operation of the rear-seat inflation
chamber.
[0019] Where the air bag has the preferable construction as stated
above, the developing/inflating operation of the front-seat
inflation chamber is also quickly started.
[0020] The inflation gas flows forward through the rear passage
above the front-seat inflation chamber and flows to the upper part
of the front-seat inflation chamber. As recalled, the guide is
formed on the peripheral wall of the gas passage located above the
plurality of inflow ports for the front-seat inflation chamber.
Therefore, part of the inflation gas flowing forward is directed
downward by the guide, and guided into the front-seat inflation
chamber, from the inflow port on the rear side. As a result, the
developing/inflating operation of the front-seat inflation chamber
is quickly started.
[0021] Also in this case, the inflation gas may smoothly be
introduced from the inflow ports into the front-seat inflation
chamber on the front side of the inflow port by appropriately
adjusting the downward projection quantity of the guide, as a
matter of course. As a result, the front-seat inflation chamber
being folded is developed downward from the substantially entire
region as viewed in the front/rear direction. This leads to quicken
the ending of the developing/inflating operation of the front-seat
inflation chamber.
[0022] Features and advantages of the invention will be evident
from the following detailed description of the preferred
embodiments described in conjunction with the attached
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In the accompanying drawings:
[0024] FIG. 1 is a front view showing a head protection air bag
device into which an air bag forming an embodiment of the present
invention is incorporated, the view being taken from the cabin
inside;
[0025] FIG. 2 is an enlarged, longitudinal sectional view taken on
line II-II in FIG. 1;
[0026] FIG. 3 is a front view showing an air bag being developed
flat which is the embodiment;
[0027] FIG. 4 is an enlarged, partial front view showing the rear
end part of the air bag being developed flat;
[0028] FIG. 5 is an enlarged, partial transverse cross sectional
view showing the air bag being inflated, the view showing an area
of the air bag taken on line V-V in FIG. 4;
[0029] FIG. 6 is an enlarged, partial front view showing the front
end part of the air bag being developed flat; and
[0030] FIG. 7 is a partial, front view showing an air bag which is
another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] An embodiment of the present invention will be described
with reference to the accompanying drawings.
[0032] An air bag 11 of the embodiment is used for a head
protection air bag device M. The air bag cover 11, while being
folded, is stored in a region including the lower fringe of a front
pillar FP, the lower fringe of the roof side rail RR, and the upper
side of a rear pillar RP, as shown in FIG. 1.
[0033] The head protection air bag device M is made up of an air
bag 11, an inflator 51, mounting brackets 46 to 48, 52, and an air
bag cover 9.
[0034] The inflator 51, as shown in FIG. 1, takes the form of a
cylinder which supplies gas for inflation to the folded air bag 11.
Gas-inflow parts 13 to be given later are attached to the air bag
11.
[0035] The mounting bracket 52 is formed with a metal sheet, and
holds down from the outer peripheral side the inflator 51 to which
the gas-inflow parts 13 (to be described later) of the air bag 11
are attached, for each gas-inflow part 13. The mounting bracket is
mounted on a sheet metal inner panel 2 of a vehicle body 1 on the
indoor side of the rear pillar RP.
[0036] As shown in FIGS. 1 and 2, the mounting bracket 46 formed
with a metal sheet sandwiches two mounting parts 12 to be described
later. The mounting bracket 46 includes an inner plate 46a on the
cabin inside IN and an outer plate 46b on the cabin outside OU.
Mount holes 46c are through formed in those inner and outer plates
46a and 46b, while corresponding to a mounting hole of each
mounting part 12. The mounting parts 12 are mounted on the inner
panel 2 in a manner that mount bolts 49 are inserted into mount
holes 12a and 46c, and screwed into a nut 2b fastened to the
circumferential edge of a mount hole 2a of the inner panel 2.
[0037] As shown in FIG. 1, the mounting bracket 47 formed with a
metal sheet sandwiches a mounting part 12, which is located at a
mid position of the air bag 11 as viewed in the front/rear
direction. It includes an inner plate 47a that is located on the
cabin inside like the inner plate 46a of the mounting bracket 46,
and an outer plate 47b located on the cabin outside. The outer
plate 47b supports a cabin-outside surface and a lower surface of
the folded air bag 11, and is shaped like L in cross section so as
to prevent it from entering the cabin outside of a garnish 6 of the
rear pillar RP when the air bag 11 is developed and inflated. Mount
holes (not attached with reference numeral) through which a mount
bolt 49 will be inserted are formed in the inner and outer plates
47a and 47b at a position corresponding to the mount hole 12a of
the mounting part 12.
[0038] As shown in FIG. 1, the mounting bracket 48 formed with a
metal sheet sandwiches two mounting parts 12, which are located at
a rear position of the air bag 11. It includes two inner plates 48a
that are located on the cabin inside like the inner plate 46a of
the mounting bracket 46, and one outer plate 48b located on the
cabin outside of the two inner plates 48a. The outer plate 48b also
supports a cabin-outside surface and a lower surface of the folded
air bag 11 like the outer plate 47b of the mounting bracket 47.
And, it is shaped like L in cross section so as to prevent it from
entering the cabin outside of the garnish 6 of the rear pillar RP
when the air bag 11 is developed and inflated. Mount holes (not
attached with reference numeral) through which a mount bolt 49 will
be inserted are formed also in the inner and outer plates 48a and
48b at a position corresponding to the mount hole 12a of the
mounting part 12.
[0039] The air bag cover 9, as shown in FIGS. 1 and 2, is defined
by the lower fringes of a pillar garnish 4 located on the front
pillar FP and a lower fringe of a roof head lining 5 located on the
roof side rail RR. The pillar garnish 4 and the roof head lining 5
are made of synthetic resin, and are secured to the inner panel 2
of the vehicle body 1, which is located on the indoor side of the
front pillar FP and the roof side rail RR.
[0040] The air bag 11 is hollow woven by using polyamide and
polyester threads. As shown in FIGS. 1 and 3, the air bag 15, as
shown in FIGS. 1 and 3, includes a main body 14, a gas inflow part
13, and a plurality of mounting parts 12. The main body 14 receives
gas for inflation from the inflator 51, and develops the folded air
bag into an inflated one to cover the opening W. The gas-inflow
parts 13 introduces the inflation gas from the inflator 51 to the
main body 14. The mounting parts 12 are provided on the upper edge
11a of the main body 14.
[0041] The gas inflow part 13 is disposed to project to the rear
end of the main body 14, and is cylindrical in shape so that it may
be applied to the inflator 51.
[0042] The plurality of mounting parts 12 are disposed projecting
above a peripheral edge part 34 on the upper edge 11a side of the
main body 14 and a plate-like member 42, which will be described
later. The mounting brackets 46, 47 and 48 used for the mount on
the inner panel 2 are secured to the mounting parts 12. The mount
holes 12a through which the mount bolt 49 will be inserted are
formed in the mounting parts 12.
[0043] The main body 14 is constructed with an inflating section 15
which communicates with the gas-inflow parts 13, receives the
inflation gas, and inflates to separate a cabin-inside side wall
15a (see FIGS. 3, 4, 5) from a cabin-outside side wall 15b, and a
non-inflating section 33 which rejects the incoming gas for
inflation.
[0044] The inflating section 15 is constructed with a rear-seat
inflation chamber 16, a front-seat inflation chamber 21, and a gas
passage 27. The rear-seat inflation chamber 16 may be arranged on
the side positions of the rear seat of the vehicle when the air bag
is developed and inflated. The front-seat inflation chamber 21 may
be arranged on the side positions of the front seat when the air
bag is developed and inflated. The gas passage 27 extends forwardly
from the gas inflow part 13, and disposed above the front- and
rear-seat inflation chambers 21 and 16, and allows inflation gas to
flow into the front- and rear-seat inflation chambers. The gas
passage 27 includes a rear passage 28, a front passage 29, and an
intermediate passage 30. The rear passage 28 is disposed above the
rear-seat inflation chamber 16. The front passage 29 is disposed
above the front-seat inflation chamber 21. The intermediate passage
30 intercommunicates the rear passage 28 and the front passage 29
above a rectangular plate portion 42b to be described later.
[0045] The non-inflating section 33 is constructed coupling the
cabin-inside side wall 15a and the cabin-outside side wall 15b. In
the embodiment, it is constructed with the peripheral edge part 34,
coupling parts 36 to 40, and a plate-like member 42. The peripheral
edge part 34 surrounds the inflating section 15. Further, it
includes a partitioning part 34a parting the space into the
gas-inflow part 13 and the rear-seat inflation section 16.
[0046] The plate-like member 42 includes a triangular plate portion
42a provided on the front side of the main body 14, and a
rectangular plate portion 40b provided under the intermediate
passage 30 between the front and rear seat inflation parts 21 and
16. The plate-like member 42 defines an overall configuration of
the main body 14 ranging from the gas-inflow parts 13 to the front
end of the main body 14. Further, it reduces a time taken till the
inflating operation ends.
[0047] The peripheral edge part 34 and the thickness defining
members 36 to 40, together with the mounting parts 12, are woven
more densely than the plate-like member 42. The plate-like member
42 is coarsely woven because it is not located at the boundary of
the inflating section 15 and hence there is no need of taking any
measure for preventing the inflation gas from leaking. It is
coarsely woven in two clothes, and those clothes are bonded
together in a spot bonding manner. In the embodiment, such
structural portions as the triangular plate portion 42a and the
rectangular plate portion 42b are disposed in the vicinity of the
mounting parts 12 on the upper edge 11a side and the gas inflow
part 13, and under the peripheral edge part 34 right under the
rear-seat inflation chamber 16 and the front-seat inflation chamber
21 of an air-bag lower fringe 11b.
[0048] The coupling parts 36 to 38 are shaped like T or J while
vertically extending within a region of the front-seat inflation
section 21. Those parts are arranged side by side as viewed in the
longitudinal direction of the vehicle, while being separated from
the peripheral edge part 34. The coupling parts 39 and 40, shaped
like I, extend downward from the partitioning part 34a of the
peripheral edge part 34 into a region of the rear-seat inflation
section 16, while being arranged side by side as viewed in the
longitudinal direction.
[0049] Those thickness defining members 36 to 40 are provided for
making even the thickness of the front and back seat inflation
parts 21 and 16 when the inflation gas flows into the inflating
section 15 to inflate it. Further, those parts cause a structure
ranging from a position near the gas-inflow parts 13 to the front
part of the main body 14 to exhibit a tension. With this, even if
such a pressing force as to press the main body 14 out of the
vehicle acts on the main body 14, the main body 14 is
immovable.
[0050] A plurality (four in the embodiment) of inflow ports 22 to
25 are formed in the front-seat inflation chamber 21. Those inflow
ports allow inflation gas to flow from the front passage 29 of the
gas passage 27 into the front-seat inflation chamber with the aid
of the coupling parts 36 to 38. The inflow port 22 is opened at a
position above and between the peripheral edge part 34 of the front
end of the front-seat inflation chamber 21 and the coupling part
36. The inflow port 23 is opened above and between the coupling
parts 36 and 37. The inflow port 24 is opened above and between the
coupling parts 37 and 38. The inflow port 25 is opened above and
between the coupling part 38 and the peripheral edge part 34 of the
front-seat inflation chamber 21. Those inflow ports 22 to 25 are
arranged such that the axial direction of those inflow ports are
vertical and substantially orthogonal to an axial direction X2 (see
FIGS. 3 and 6) of the front passage 29 of the gas passage 27, which
is disposed in the front/rear direction (substantially
horizontal).
[0051] In the embodiment, the inflow port 25 located at the rear
end of the front-seat inflation chamber 21 is located at the
position of a center pillar CP when the air bag 11 is mounted on
the vehicle.
[0052] One inflow port 17 is bored in the upper part of the front
side of the rear-seat inflation chamber 16. The inflow port 17
allows inflation gas to flow from the rear passage 28 of the gas
passage 27 to the rear-seat inflation chamber. The axial direction
of the opening of the inflow port 17 is vertical and substantially
orthogonal to the axial direction X1 (FIGS. 3 and 4) of the rear
passage 28 of the gas passage 27, which is disposed in the
front/rear direction (substantially horizontal).
[0053] The front-side peripheral edge 18 of the inflow port 17 of
the rear-seat inflation chamber 16, as shown in FIG. 4, is higher
than the rear-side peripheral edge 19 by a dimension of H1 (20 mm
in the embodiment) in a state that the air bag 11 is developed
flat.
[0054] The peripheral edge 18 of the peripheral edge of the inflow
port 17 is positioned at the uppermost position of the peripheral
edge part 34 which defines the front end of the rear-seat inflation
chamber 16, and in the embodiment, it is on the same level with a
beginning part 34b of the partitioning part 34a, which is closer to
the gas inflow part 13. The rear-side peripheral edge 19 of the
peripheral edge of the inflow port 17 is positioned at the fore end
of a linear part 34c of the partitioning part 34a, which linearly
slants downward from the beginning part 34b. In this embodiment,
the peripheral wall of the rear passage 28 (an upper edge 34d of
the peripheral edge) is linearly and horizontally extended. The
partitioning part 34a forming the peripheral wall on the lower edge
side of the rear passage 28 is configured such that the linear
intermediate part 34c is extended obliquely and downward, and the
rear passage 28 is expanded in diameter toward the front side.
Accordingly, the front-side peripheral edge 18 is higher than the
rear-side peripheral edge 19 by the dimension H1.
[0055] In the embodiment, as shown FIGS. 3 and 6, above the inflow
port 25 on the rear side of the front-seat inflation chamber 21, a
guide 31 is formed on the peripheral wall on the upper edge side of
the front passage 29 of the gas passage 27. The guide 31 is
configured such that the peripheral edge part 34 is gently inclined
downward from the intermediate passage 30. The guide 31 is provided
to positively direct downward part of the inflation gas flowing
forward within the intermediate passage 30 and guide the gas from
the inflow port 25 to the front-seat inflation chamber 21.
[0056] In the embodiment, a downward projection quantity H2 between
the lower end 31a of the guide 31 and the peripheral wall of the
intermediate passage 30 on the upper edge side is set at 30 mm.
[0057] The intermediate passage 30 is configured such that the
lower peripheral wall is slanted downward more sharply than the
guide 31 so as to increase its diameter to the front. In other
words, the front end of a mid position 34e on the upper side of the
rectangular plate portion 42b of the peripheral edge part 34, is
greatly bent downward.
[0058] In the embodiment, as indicated by a two-dot chain line in
FIG. 3, folding of the air bag is repeated in opposite directions
and holding edges C are formed at the crests and troughs, whereby
the air bag is formed like bellows acting so as to move the lower
edge of the 11b to the upper edge 11a. In manufacturing the air bag
11, a base cloth is woven to have a predetermined pattern. Then, if
required, it is processed to increase its heat resistance, and is
coated with silicone or the like to form a coating layer thereon in
order to prevent the inflation gas from being leaked. Incidentally,
after the base cloth is woven, the coating layer is formed over the
outer surface of the base cloth because it is impossible to coat
its inner surface with coating material.
[0059] After folded, the air bag is wrapped with a tape 44 which
may be broken (FIGS. 1 and 2), in order to prevent its
re-expansion. Then, the inflator 51 and the mounting brackets 46 to
48, and 52 are mounted on it, whereby an air bag assembly is
formed. A tape 44 which may be broken, is further applied to the
areas of the mounting brackets 47 and 48 so as to prevent those
mounting brackets 47 and 48 from separating from the air bag
11.
[0060] The mounting brackets 46 to 48, and 52 are located at
predetermined positions of the inner panel 2; The mount holes 12a
or the like are passed therethrough and fastened by bolts 49 and
53; and the mounting brackets 46 to 48; and 52 are fastened to the
inner panel 2, whereby the air bag assembly is mounted to the
vehicle body 1. Thereafter, the pillar garnish 4 and the roof head
lining 5 are attached to the vehicle body 1. Further, a rear pillar
garnish 6 and a center pillar garnish 7 are attached to the vehicle
body 1. Here, the air bag 11, together with the head protection air
bag device M, has been mounted on the vehicle.
[0061] The head protection air bag device M is mounted on the
vehicle, and the inflator 51 is operated. An inflation gas G output
from the inflator 51 flows from the gas-inflow parts 13 and through
the gas passage 27, i.e., the rear passage 28, the intermediate
passage 30 and the front passage 29 in this order. The gas flows
out of the inflow ports 22 to 25 in the form of branch streams G1
to G4 of the gas, and reaches the front-seat inflation chamber 21.
A branch stream G5 of the gas flows out of the inflow port 17 and
into the rear-seat inflation chamber 16. The inflating section 15
starts to inflate while bringing out of its folded state. The air
bag 11 breaks the tape 44 with which the air bag is wrapped;
forcibly opens the pillar garnish 4 and the air bag cover 9 on the
lower edge side of the roof head lining 5; and greatly inflates so
as to cover the opening W and the cabin-inside side of the rear
pillar RP, while projecting downward.
[0062] In the embodiment, the inflow port 17 of the rear-seat
inflation chamber 16 is opened to the gas passage 27 of the air bag
11 in the direction substantially orthogonal to the axial direction
X1 of the gas passage 27 (rear passage 28), which is disposed in
the front/rear direction. The front-side peripheral edge 18 of the
inflow port is lower than the rear-side peripheral edge 19 by the
dimension H1. Accordingly, the front-side peripheral edge 18 of the
inflow port 17 is easy to interfere with the inflation gas G by an
extent corresponding to the dimension H1 by which the front-side
peripheral edge 18 is higher than the rear-side peripheral edge 19.
The front-side peripheral edge directs the inflation gas G5
resulting from the interference to the rear-seat inflation chamber
16. This leads to a quick start of the developing/inflating
operation of the rear-seat inflation chamber 16.
[0063] The inflow port 17 of the rear-seat inflation chamber 16 has
merely such a configuration that it is opened in the direction
substantially orthogonal to the axial direction X1 of the gas
passage 27 (rear passage 28), and its front-side peripheral edge 18
is higher than its rear-side peripheral edge 19. Such a
configuration of the inflow port cannot direct the entire inflation
gas G flowing forward within the gas passage 27 to the rear-seat
inflation chamber 16, as a matter of course. Therefore, a delay of
the ending of the developing/inflating operation of the front-seat
inflation chamber 21 may be minimized by appropriately adjusting a
height of the front-side peripheral edge 18 from the rear-side
peripheral edge 19.
[0064] Accordingly, the air bag 11 of the embodiment which is used
for the head protection air bag device M is capable of minimizing
the delay of the ending of the developing/inflating operation of
the front-seat inflation chamber 21, and quickly starting the
developing/inflating operation of the rear-seat inflation chamber
16.
[0065] The dimension H1 of the front-side peripheral edge 18 of the
peripheral edge of the inflow port 17 of the rear-seat inflation
chamber 16 from the rear-side peripheral edge 19 is preferably 15
to 40% of the dimension B1 of the opening of a general portion 28a
(front-side peripheral edge 18 or beginning part 34b) of the rear
passage 28 in a state that the air bag 11 developed flat. If the
height H1 is smaller than 15%, the effect of securing the quick
start of the developing/inflating operation of the rear-seat
inflation chamber 16 is lessened. If it is in excess of 40%, its
interference with the inflation gas G flowing to the front-seat
inflation chamber 21 is large. As a result, there is a danger of
delaying the ending of the developing/inflating operation of the
front-seat inflation chamber 21.
[0066] In the air bag 11 of the embodiment, the front-seat
inflation chamber 21 is opened in the direction substantially
orthogonal to the axial direction X2 of the gas passage 27 (front
passage 29). A plurality of inflow ports 22 to 25 are arrayed along
the front passage 29 of the gas passage 27. Provided above the
inflow port 25 on the rear side is the guide 31 for directing
downward part G4 of the inflation gas G flowing forward and guiding
the gas from the inflow port 25 on the rear side into the
front-seat inflation chamber 21.
[0067] The inflation gas G flows forward through the rear passage
28 above the front-seat inflation chamber 21 and to the front side
of the intermediate passage 30. When the inflation gas G flows to
the upper part of the front-seat inflation chamber 21, part G4 of
the inflation gas G flowing forward is directed downward by the
guide 31, and guided into the front-seat inflation chamber 21, from
the inflow port 25 on the rear side. As a result, the
developing/inflating operation of the front-seat inflation chamber
21 is quickly started.
[0068] Also in this case, the inflation gases G1 to G3 may smoothly
be introduced from the inflow ports 22 to 24 into the front-seat
inflation chamber 21 on the front side of the inflow port 25 by
appropriately adjusting the downward projection quantity H2 of the
guide 31, as a matter of course. As a result, the front-seat
inflation chamber 21 being folded is developed downward from the
substantially entire region as viewed in the front/rear direction.
This leads to quicken the ending of the developing/inflating
operation of the front-seat inflation chamber 21.
[0069] The quantity H2 of the downward projection of the lower end
31a of the guide 31 from the intermediate passage 30 is preferably
20 to 50% of the opening dimension B2 of a general portion 29a
(portion of the upper end of the coupling parts 36 to 38) of the
front passage 29. If it is smaller than 20%, the effect of securing
the quick start of the developing/inflating operation of the
rear-seat inflation chamber 16 is less effected. If it is in excess
of 50%, its interference with the inflation gas G flowing to the
front side of the front-seat inflation chamber 21 is large. As a
result, there is a danger of delaying the ending of the
developing/inflating operation of the front-seat inflation chamber
21.
[0070] In the above-mentioned embodiment, the inflow port 17 of the
rear-seat inflation chamber 16 is located on the front side
thereof. If required, the inflow port 17 may be located on the rear
side of the rear-seat inflation chamber 16 as shown in FIG. 7. Also
in this case, the front-side peripheral edge 18 of the peripheral
edge of the opening of the inflow port 17 is selected to be higher
than the rear-side peripheral edge 19 by the height H1.
[0071] In the embodiment mentioned above, the coupling parts 39 and
40 of the rear-seat inflation chamber 16 are linearly and
vertically extended. In an alternative, those coupling parts 39 and
40 may be extended vertically while being curved, as shown in FIG.
7. The same thing is true for the coupling parts 36 to 38 within
the front-seat inflation chamber 21.
[0072] In the embodiment, a hollow weave air bag is used for the
air bag 15. The air bag may be formed by stitching, adhering using
adhesive, welding using high frequency welder or another suitable
process. In this case, the invention may be applied to the
configuration of the peripheral edge of the inflow port.
[0073] Although the invention has been described in its preferred
form with a certain degree of particularity, it is understood that
the present disclosure of the preferred form can be changed in the
details of construction and in the combination and arrangement of
parts without departing from the spirit and the scope of the
invention as hereinafter claimed.
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